A tremendous amount of current research is directed at devising corrective or compensatory genetic or therapeutic interventions in genetically altered mouse models of human disease. One of the major problems in the field is the absence of a reliable method to uniformly deliver genetic material across the plasma membrane, especially in nondividing cells such as neurons. We have developed an anionic liposomal delivery system that can package and deliver genetic material uniformly to cultures of postmitotic neurons. These anionic liposomes enter neurons via constitutive endocytosis and present no in vitro toxicity of their own. This novel delivery system holds great potential for effecting uniform transfection of mature neurons in vivo. The experiments proposed in this grant seek to test this delivery system for the introduction of genetic material into the mouse CNS. These experiments will lay the groundwork for the future therapeutic delivery of genes and antisense oligonucleotides targeted to a. variety of hereditary neurodegenerative diseases. Our long range goal is to develop this technique for both experimental and clinical genetic manipulation. Our current objective is to test this technology to assess its limits and to optimize the formulation and delivery method for maximal CNS transfection. Attainment of this objective will define the optimal protocol for applying this technology to CNS gene delivery. We will then be in a position to apply it to animal models of trinucleotide repeat diseases to compare the growing number of proposed genetic interventions for the treatment of Huntington's Disease and spinocerebellar ataxia. Towards this goal, we propose to determine if DNA encapsulated in anionic liposomes can be delivered into cells in the striatum and cerebellum and the extent of tissue penetration and transfection that can be achieved with different routes of CNS entry.